At 5:30 this morning the bit hit bottom and we started drilling ahead! We are currently at 12,250 ft and making good progress while the science team gets back to work collecting and analyzing new samples.
Reaming operations were completed overnight, and the open hole between the casing shoe at 10,005 ft and our current depth of 12,181 ft is in good shape. We are now tripping out of the hole to install the steerable drilling assembly.
Activities at the site today included checking the bottom hole assembly, tripping in the hole for a reaming run, and conditioning the drilling mud. We should be reaming overnight and then going back into the hole to resume drilling tomorrow.
At 12:45 this afternoon, we started tripping out of the hole, having successfully retrieved the drill pipe and bit that had been stuck in the hole. It will take some time to work on the mud system and check the bottom hole assembly. We will then attempt to ream and condition the hole again. If that is successful, drilling will likely resume in 36 to 48 hours.
The first step in the process of getting unstuck went very well today. The pipe was successfully ""backed off"" one section of drill pipe below the drilling jars at a depth of 11,658', as intended. About 350' of pipe, and the bit, are left in the hole. We know from the logging-while-drilling data that the section of the hole that contains ""the fish"" was in good shape at the time it was drilled (the hole size was almost everywhere in gauge). There are several sections of enlarged hole, but these extend over relatively short intervals. We are tripping into the hole with heavy duty jars, an intensifier and bumper sub to try to retrieve the fish.
Wellbore stability problems developed during the bit trip Saturday, making it necessary to back-ream out of the hole. The trip out was completed successfully despite two very tight intervals where the pipe was stuck briefly. This morning, a reaming trip was started in order to clean out the well and circulate in slightly denser mud. During the reaming trip into the hole, with the bit at a depth of 12,030 feet (~150 feet off bottom) the pipe got stuck. Actions are currently being taken to remedy the situation.
After drilling to 12,180 feet we are tripping out of the hole to change the bit again. We'll be back on bottom and drilling tomorrow morning. Although a significant change in lithology occurred at 12,120 ft, we do not appear to have crossed the San Andreas fault yet.
The last drilling phase (bit #8) ended several hours prematurely yesterday when the drill pipe showed a sudden increase in torque. When the pipe was tripped out of the hole, it was discovered that the drill bit had lost one of its three cones. This has caused a delay of about 18 hours as we've needed to make a trip into the hole with a mill to grind up the cone on the bottom. We expect to resume drilling at around midnight.
Another bit trip gives us a brief reprieve from the intense scientific activity of the last few days, including sample collection under a full moon. We will be back on site when drilling resumes in the early morning hours tomorrow.
It was a busy day at SAFOD as we started drilling with a new bit, finalized some of our procedures for on-site, real-time mineralogical analysis, and had lots of visitors. Our current depth is 11,716 feet, and we're advancing at 5 to 10 feet per hour.
Drilling continues slowly but steadily at rates between 3 and 7 feet per hour. We'll change the bit tonight and resume drilling tomorrow afternoon. Meanwhile we're using our scientific creativity to develop analysis techniques with materials we have on hand.
The science team excitedly started collecting cuttings again today as drilling resumed from a depth of 11,462 ft. With real-time mineralogical and gas analysis, we are scrutinizing the material we drill through. Our goal is to identify fault materials as early as possible.
The data from the first LWD run were dowloaded successfully and reveal important geological characteristics and potential shear zones in the Phase II hole. Drilling and logging are set to resume tonight or early tomorrow morning. The brief hiatus provided the geology team time to generate and closely examine thin sections of the cuttings.
While the drilling crew has been pulling out of the hole to change the bit and download the LWD data, the science team has been busy setting up equipment for real time mineralogic analyses of the cuttings that will aid in identifying the fault.
Drilling continues with LWD. A team of geologists, with additional analytical equipment, have arrived on site to assist in real time lithologic analyses as we approach the San Andreas Fault.
We have been Logging While Drilling (LWD) since last night and will soon complete logging in the already-drilled section of the borehole. Once TD is reached, rotary drilling with LWD will commence and the science team is anxiously watching the real-time logging data help characterize the rocks in the San Andreas Fault Zone as they are penetrated by the borehole.
After a successful reaming trip the Schlumberger field engineers are making the final preparations to the LWD logging tools in anticipation of beginning the logging run around midnight.
The crew is carrying out a variety of tasks while preparing for a trip into the hole to condition the mud (after the appreciable down time) and hole reaming (following the directional drilling that preceded the top drive going down), all in preparation for the resumption of drilling with LWD (logging while drilling) tools on Sunday or Monday.
Today the rig crew is reinstalling the repaired top drive and we are set to resume drilling towards the San Andreas fault. We anticipate that we will begin reaming and conditioning the hole later this evening.
Unfortunately the top drive is giving us trouble again. The motor failed and must be repaired in Bakersfield. Due to this, drilling operations will be put on standby for a few days. We plan to be drilling again by the end of the week. We will continue posting updates when the drilling resumes.
After two and half hours spent trying to retrieve a core, unforseen problems stymied our attempt and at 7pm this evening the core barrel was pulled out of the hole and contained only a few rock fragments. Nonetheless, scientists are excited about analyzing the gas content and mineralogy of these rocks from the crust adjacent to the fault zone. We are now proceeding to ream and condition the hole in preparation for the LWD as we continue our journey to the San Andreas Fault.
The top drive has been repaired, a new schedule has been set for the coring run. The borehole conditions have been evaluated, and are optimal to proceed with the coring. Tonight we will start the core run!
The drilling operations were forced to stop due to a failure in the top drive transmission system. The top drive must be repaired in Bakersfield, which will take several days. The failure occurred when we were about to start coring, which forced us to delay the coring schedule. Hopefully, the coring and Logging While Drilling will start sometime next week. We will be offline while the top drive is being repaired.
Today we reached a measured depth of 11,270 ft. We have stopped drilling and are now rigging up for coring. Around midnight we will start the first core run for Phase II of the SAFOD project!
Drilling goes on as planned. The last sample came from a measured depth of 11,000 ft ! We are drilling through fine grained sediments. The first samples have already been sent the USGS office in Menlo Park for XRD analyses. Each day we are closer the San Andreas fault zone!
Equipment and staff are beginning to arrive for coring operations and LWD deployment, which will take place after this latest bit wears out. Meanwhile, over the next two days we will continue to make new hole and collect cuttings samples for petrographic, X-ray diffraction, and other analyses.
Today was a ""No News is Good News"" day here at the site. We are making consistent drilling progress with a steady rate of penetration of about 10 ft/hr, and we've been in a fine-grained, sedimentary lithology since late last night. We will probably need to change bits tomorrow, and then we will proceed to drill to 11,150 ft before we begin our first Phase II coring effort.
It was back to business here at SAFOD today, as we drilled ahead approximately 60 ft this afternoon and plan on making plenty of progress throughout the next couple of days. We've gone from a dark, shaly formation to a lighter sandstone or quartzite. A variable rate of penetration suggests that we are changing lithologies quickly and/or going through a highly fractured material. Further drilling will help us better understand how close we are getting to the San Andreas!
Today was a slow day for the scientists. The drillers are reaming the well below the 10,005 ft casing shoe, and we will resume drilling as soon as that is completed.
Our drilling crew worked hard today to free the drill pipe from a tight spot below the last casing shoe at 10,005 ft. Now we are pulling out of the hole to install a new bit before resuming drilling. Our current hole depth is 10,484 ft.
All of us at SAFOD send out a hearty congratulations to our own Naomi Boness, who was hooded by Mark Zoback at Stanford's commencement ceremony Sunday.
Preparations for the SAFOD Phase II well continued today. The science team is anxious to see some new samples, and we anticipate drilling will begin within the next 24 hours.
As the start of drilling approaches mud engineer Alan Bartley is preparing the drilling mud while the scientists and mudloggers are fine tuning their labs.
It's been a very full 24 hours, starting with fluid sampling in the early morning hours and ending with a hydrofrac scheduled for late tonight. The fluid sampling went very well, capturing both pore fluids and gases from the bottom of the 10,000-foot well.
Our drilling crew lowered over 10,000 feet of pipe into the well today! Fluid sampling operations will take place throughout the night. We're on a 24/7 schedule here at SAFOD.
The site was a busy place today as final preparations were made to the rig, drilling pipe was unloaded, and scientists started arriving for upcoming fluid sampling and hydrofracturing experiments.
The Phase II drilling season for the SAFOD Main Hole has begun!!! Today we had two kinds of drives on site - a top drive and a cattle drive (see additional photos)! The rig is up, and preparations are in full swing. We expect to get the science under way within the next 48 hours. Please check back for daily updates.
Scientists from across the US met at the core repository in Texas A&M University to examine the cores from Phase 1 of drilling. Meanwhile preparations for Phase 2 drilling are ramping up. The site characterization team is preparing for the last suite of experiments designed to accurately locate the target earthquakes.
This will be our final daily update from the SAFOD drill site for the Phase 1 drilling campaign. Phase 2 activities will commence around June 1, 2005. In the interim, please check this website for updates, as information will be posted periodically during this drilling hiatus.
In the past two weeks, the hole was successfully logged, casing was installed to 10,010 ft MD, and 38 feet of core was obtained from the bottom of the hole. In addition, a fiber optics laser
Over the next week, a long-term fluid build up test will be initiated and the hole will be secured for the winter. Nabors Rig 633 will be released in a few days. On October 15th, a seismic monitoring sonde will be installed in the hole to record both earthquakes and shots set off at some of the
surrounding surface seismic stations. In preparation for next summer's drilling, these data will be used to further refine geophysical models of the region near the San Andreas fault and improve
